Apparatus and method for generating vibrations



g- 12, 1969 R. L. WILDE 3,460,808

APPARATUS AND METHOD FOR GENERATING VIBRATIONS Fiied June 23, 1966 4Sheets-Sheet 1 INVENTOR. ROBERT L. WILDE A TTORNEYS' g- 1969 R. L. WILDE3,460,808

APPARATUS AND METHOD FOR GENERATING VIBRATIONS Filed June 23, 1966 4Sheets-Sheet 2 INVENTOR. ROBERT L. WILDE lah Mad A TTORNEYS R. L. WILDEAPPARATUS AND METHOD FOR GENERATING VIBRATIONS Filed June 23, 1966 4Sheets-Sheet 3 INVENTOR.

ROBERT L. WILDE way/6w A TTORNEYS Aug; 12, 1969 R. L. WILDE ,460,8

APPARATUS AND METHOD FOR GENERATING VIBRATIONS Filed June 23, 1966 4Sheets-Sheet 4 INVENTOR.

ROBERT L. WILDE B) ATTORNEYS United States Patent ice US. Cl. 259-4 26Claims ABSTRACT OF THE DISCLOSURE An apparatus for generating vibrationsutilizing an inertia ring mounted for orbital movement relative to amember wherein a work chamber is formed between the opposed surfaces ofthe ring and the member, said apparatus being characterized in the useof means for moving the ring orbitally relative to the member whilemaintaining at all times during such movement a predetermined amount ofminimum separation between the opposed surfaces of the ring and themember. The means for moving the ring orbitally relative to thememberincludes means for supplying to the motor cavity, during at leastapproximately one-half of each cycle, a predetermined amount of fluid ofsubstantially constant pressure without substantially any linear massvelocity, the volume of fluid equaling the instantaneous volume of themotor cavity whereby the increase volume of fluid, to be disposed withinthe motor cavity, occurring from expansion of the fluid substantiallyequals the increased volume of the motor cavity during movement of thering. The means for moving the ring orbitally relative to the memberalso includes means for effecting at least a partial decompression ofthe motor cavity and exhausting the exhaust cavity.

This invention lies in the field of vibration generators such as thoseused in compacting freshly poured concrete and operating shakingmachines of various types but is not limited thereto. It is directedparticularly to the type of apparatus in which a component ofsubstantial mass is moved in an orbital path with respect to the balanceof the apparatus to produce alternating force resultants in oppositedirections. More specifically it is directed to the type of vibrator inwhich an inertia ring is caused to gyrate about a central core in anorbital path, using compressed fluid as the power source.

Devices of the type mentioned above are generally classed as rotaryvibrators because in fact the unbalanced weight component has an axlewhich is mounted in hearings to allow rotation of the component, or thecomponent actually rolls around a track of some kind. In one form, asolid or hollow cylindrical Weight rolls in contact with the inner wallof a cylinder of larger diameter. In another form, a hollow cylindricalWeight in the form of a ring rolls in contact with a core having adiameter less than the inside diameter of the ring.

The various types of vibrators mentioned above perform their intendedfunctions quite well but they have drawbacks which reduce theirefliciency or service life and in many cases are far more complicatedmechanically than their basic-operation can justify. The multiplicity ofmoving parts is one of the factors increasing the maintenance costs.Another is the fact that the parts which roll on each other are subjectto rather heavy loads by the very nature of the operation, the wholepurpose of which is to produce unbalanced loads. The wear on these partsis very rapid. When an excessive amount of pressure fluid is introducedin each cycle of operation, efficiency is reduced because only a lowproportion of the available expansion energy in the compressed fluid isutilized. On the other hand, if insufficient pressure fluid isintroduced,

3,460,808 Patented Aug. 12, 1969 the power output is less than thetheoretical capacity of the apparatus.

The present invention overcomes the disadvantages mentioned above byproviding an apparatus which operates on the same broad principles asother inertia ring types but which encounters a minimum of wear by usingthe pressure fluid as a lubricant and as a natural mass preventingdirect physical contact between the moving inertia ring and thestationary supporting member. The extent and timing of the opening ofthe inlet and outlet ports is such as to insure entry of the properamount of working fluid in each cycle and adequate provision forexhausting the fluid at the proper time in the sequence. Moreover thisis accomplished with a minimum of complexity, there being only twomoving parts in the as sembly.

. Briefly and generally stated, the apparatus comprises a spool-shapedsupporting member having a central cylindrical core and a pair oflaterally extending end walls defining a cylindrical work chamber. .Aninertia ring is mounted in the work chamber for free oscillatorymovement in any direction radial of the core. To provide for this freemovement, the inner diameter of the inertia ring is substantially largerthan the diameter of the core, and the length of the ring is slightlyless than the longitudinal distance between the inner faces of the endwalls. Thus the ring can gyrate about the core, following an orbitalpath, and produce centrifugal force successively in all directionsradial of the core, the force being transmitted to the core and itsassociated elements through the medium of the mass of compressed fluid,which then apply the force externally for useful purposes such ascompacting freshly poured concrete.

To drive the ring in its orbital movement it is necessary to provide amotor cavity and an exhaust cavity and to supply fluid under pressure tothe motor cavity, the fluid being discharged out of the exhaust cavityafter it has done its work. For these purposes a guide slot is formed inthe core extending longitudinally between the end walls and extendingradially from a location near the axis of the core to the surface of thecore. A barrier blade is mounted in the slot with sufficient clearanceto permit it to move readily in a radial direction. The blade ispreferably flat and rectangular in planform and is slightly shorter thanthe axial distance between the end walls to provide clearance at eachend of the blade. The outer free edge of the blade is straight andsmooth and adapted to contact the inner surface of the inertia ring insealing engagement at all times during operation to define the initialpoint of a motor cavity of variable volume and peripheral extent betweenthe core and the inertia ring and the end point of an exhaust cavity ofvariable volume and peripheral extent between the core and the inertiaring.

Inlet and outlet ports are provided in one end wall, and in thepresently preferred embodiment are provided in both end walls. The inletport communicates with the work chamber on the motor side of the bladeand the outlet port communicates with the work chamber on the exhaustside of the blade. The inertia ring is of such radial thickness that itsend face completely covers the inlet and outlet ports when the ringclosely approaches the core in the zone of each respective port. Whenthe ring is spaced the maximum distance from the core in the zone ofeach port, it partially uncovers the port for the passage of fluid. Theend face of the ring thus serves as the sole valving means for each ofthe ports and it successively opens and closes them at the proper timeand to the proper extent during each cycle of its gyrations. The inletport is in communication with a source of compressed fluid by way of afluid passage.

The size, shape, location and relative attitude of the inlet and outletport are so chosen that there is always in the work chamber between thering and the core a sufficient mass of pressurized fluid to transmit thecentrifugal force of the ring to the core while maintaining themslightly separated at the zone of closest approach. Hence the ring doesnot roll on the core, thus preventing the wear which would otherwiseoccur. Actually the ring need not rotate about its own axis in operationbecause it is free floating and oscillatory in nature.

In order to achieve maximum uniformity of operation the condition of thepressure fluid is modified in its travel from the source to the inletport. As is known, flowing compressed fluid possesses both the kineticor velocity energy resulting from its rate of flow and the potentialexpansion energy resulting from its compression. It has been found thatthe linear mass velocity of flow through a channel or passage is highlyvariable and to a great extent uncontrollable. On the other hand, thevelocity of pure expansion is limited by a unique circumstance. At anyconstant temperature, if the back pressure or dumping area pressure isabout one half the pressure of the compressed fluid or less, then thefluid will expand into the dumping area at a fixed velocity throughout awide range of pressures, the velocity of expansion being related to themolecular, or atomic orbital velocity of the composition of the selectedfluid.

It is therefore desirable to transform as much as possible of thevelocity energy into potential expansion energy before utilizing thepressure fluid. This is done by incorporating an expansion chamber closeto the inlet port. The chamber is much larger than the flow passage andis so arranged that the pressure fluid not only expands into it,transforming a major portion of the velocity energy into potentialenergy, but also encounters an abrupt change of direction which furtherreduces the velocity energy. Thus the primary action of the fluid in thework chamber is based on pure expansion velocity which produces a veryuniform rate of operation.

Various other advantages and features of novelty will become apparent asthe description proceeds in conjunction with the accompanying drawings,in which:

FIGURE 1 is a sectional elevational view of the apparatus embodying theinvention;

FIGURE 2 is a sectional view taken on line 22 of FIGURE 1;

FIGURE 3 is an exploded view in perspective of the principal workingparts of the apparatus;

FIGURES 4 to 9 are schematic views illustrating the relation of parts atvarious stages in one cycle of operation;

change in relation of parts under reduced load; and

FIGURE 12 is a schematic view illustrating a modification of the inertiaring and barrier blade.

One presently preferred form of the apparatus is illustrated somewhatschematically in section in FIGURE 1, in which the spool-shapedsupporting member comprises an axle member 10 having an enlargedcentrally located cylindrical core 12 and reduced first and second ends14 and 16, on which are mounted end walls or plates 18 and 20. The endwalls fit snugly on the axle ends and are held tightly in engagementwith the core by the threaded members 22 and 24. The flat, laterallyextending inner faces 26 and 28 of members 18 and define with thesurface of core 12 a cylindrical work chamber 30. A cylindrical inertiaring 32, with cylindrical inner and outer faces 34 and 36 and flat,laterally extending end faces 38, is mounted for oscillating movement inan orbital path within the work chamber.

The inner diameter of the inertia ring is substantially larger than thediameter of the core to permit substantial movement of the ring in alldirections radial of the core, and its length in an axial direction isslightly less than the longitudinal distance between the inner faces 26and 28 of the end walls to provide adequate clearance. In operation thering oscillates or gyrates about the core in an FIGURES 10 and 11 aresimilar views illustrating the r orbital path in response to forceexerted by pressure fluid admitted to the work chamber. In a sense itcan be said to swing about the core so that it is always eccentricallylocated with one portion of its inner surface 34 always quite close tothe surface of the core but separated by a small gap 40 for reasons tobe explained later. The gap zone, of course, travels continually aroundthe periphery of the core as the ring oscillates. A casing 42 having aclosed end 44 snugly surrounds end walls 18 and 20 and completes theenclosure of the work chamber. A second casing member 46 forms acontinuation of casing 42 to enclose the entire apparatus.

Means to provide pressure fluid to the work chamber includes a fluidpassage 48 extending longitudinally through the axle member and slightlydisplaced laterally from its axis. The passage is divided into threesections. The first and largest section 50 is at end 16 of the axle andreceives pipe 52 which transmits compressed fluid from a source notshown. The pipe is mounted Within the neck 54 of easing member 46 bymeans of a spider fitting 56 and is sealed to the axle by conventionalO-rings 58. The pressure fluid may be any suitable compressible fluidbut preferably is air because of cheapness and availability. Aircompressors are almost universally available at construction sites andusually provide air at pressures of 90 to 120 p.s.i.

Since section 50 is considerably larger than the passage in pipe 52 itserves as an expansion chamber which transforms much of the velocityenergy of the mass flow into potential expansion energy. Passage 60 inend wall 20 extends laterally from chamber 50 and then axially intoinlet port 62 which opens into the work chamber 30. These two bendswhich change the direction of flow serve to further transform velocityenergy into potential expanslon energy.

Central section 64 of passage 48 is considerably smaller than section 50because approximately half of the total flow of fluid is diverted intopassage 60. End section 66 is smaller than section 64 to maintain ahigher pressure in the latter for reasons to be mentioned later. Section66 discharges into expansion chamber 68 which serves in the same way assection 50 to change the direction of flow and transform velocity energyinto potential expansion energy. Inlet port 70 communicates directlywith chamber 68 to admit pressure fluid into the work chamber. It islocated directly opposite inlet port 62 and is of the same size andshape to provide balanced flow of pressure fluid.

A rectangular slot 72 is formed in core 12 and extends longitudinallyfor the length of the core and radially to its outer surface from alocation near the core axis. Barrier blade 74 is mounted in the slot andis in the form of a fiat rectangular plate slightly shorter than thedistance between the end walls to provide clearances 76. Its outer freeedge 78 is straight and smooth for sealing contact with the innersurface 34 of the inertia ring. Auxiliary ports 80 and 82 are formed inend walls 1 8 and 20 in axial alignment with the blade to lead pressurefluid to clearances 76. The balanced pressure against the two ends ofthe blade centers it and keeps it clear of the end wall faces tominimize friction.

In order to maintain the free edge 78 of the blade in sealing contactwith the inner surface of the inertia ring at all times during operationit is necessary to provide means to yieldingly urge it outward. Thebottom portion of slot 72 forms a pressure chamber 84 fed with pressurefluid from section 64 by way of apertures 86. The back pressure in 64resulting from the constriction in section 66 aids this operation. Inaddition passage 88, adjacent to slot 72, communicates at its lower endwith section 64 and at its upper end with the work chamber for reasonsto be detailed later.

The relationship of the parts just described is further illustrated inFIGURES 2 and 3, where it will be seen that inlet ports 62 and 70include slots having a generally arcuate form extending peripherallypart way around the core. Each port is on the motor side of the blade74, originates adjacent thereto, and extends about sixty degrees. It isarranged eccentrically or spirally so that the end adjacent to the bladeis closer to the core. It will be apparent that in all positions of theinertia ring, its end faces cover some portions of ports 62 and 70 sothat fluid pressure is exerted against the end faces and a small portionof the fluid passes through clearances 76 with the result that the ringis always spaced from the end walls and develops no friction. Aplurality of passages 90 are arranged peripherally around the end walland at least some of them are partially uncovered at all times so thatthe leakage fluid can discharge.

Outlet ports 92 and 94 are also elongate and generally arcuate orspiral. They extend peripherally around the core about one hundredeighty degrees with terminal ends adjacent to the blade 74 on theexhaust side and closer to the core than the originating ends. With theinertia ring and the blade in the positions shown in FIGURES 2 and 3they combine with the core to form a motor cavity 96 to the left of theblade between the ring and the core and an exhaust cavity 98 between thering and the core to the right of the blade. The orbital movement of theinertia ring is counterclockwise as viewed in these and subsequentfigures. In FIGURE 2 it will be seen that both the inlet and outletports are partially uncovered or opened. Thus pressure fluid enters themotor cavity and the expanded fluid passes out of the exhaust cavitythrough ports 92 and 94. Returning to FIGURE 1, it will be seen thatoutlet port 94 cannot be open entirely through its end wall 18 becauseit would communicate with expansion chamber 68. Therefore cross passages100 are provided which connect with auxiliary outlet passages 102 in thecore and 104 in end wall 20. All of the exhaust fluid finally passes outthrough casing member 46 and neck 54.

The sequence of steps which produce the gyratory motion of the inertiawheel are schematically illustrated in FIGURES 4 to 9, with theapparatus operating at full design load. For purpose of explanation itwill be considered that the arrangement of FIGURE 4 represents the zerodegree position and the 360 degree position. At this stage the inertiaring is in its uppermost position, being held out of contact with thecore, as indicated at gap 40, by the fluid pressure as previouslyexplained. Blade 74 is in its uppermost position in sealing contact withthe ring, and the motor cavity 96 and exhaust cavity 98 are exactlyequal in size. Inlet port 62 is open to its maximum extent, and thepressure fluid is entering and expanding to increase the size of themotor cavity. Outlet port 92 is open slightly less than its maximumextent, allowing the fluid to exit so that the exhaust cavity candecrease in volume.

FIGURE 5 represents the 60 degree stage. The inlet port is still wideopen and the motor cavity has been enlarged. The outlet port and theexhaust cavity have been decreased in size. At this point the inlet portbegins to close, and it will be seen that at the 120 degree position ofFIGURE 6 the inlet port is closed while the pressure remaining in themotor cavity causes the cavity to generate counterclockwise inaccordance with a constantly increasing exhaust port which becomesstatic at FIGURE 9 as the inlet port begins to open.

At FIGURE 7 the 180 degree position has been reached, the inlet port isstill closed, and there is only one cavity, which is open to exhaust. Asthe ring passes this stage, the motor cavity of the next cycle begins toform but the increase is small, and fluid entering through passage 88from passage 64 is sufiicient to provide the motive power. At FIGURE 8and 240 degrees inlet port 62 is still closed but outlet port 92 is wideopen. At 270 degrees, not shown, the inlet port again begins to open andis partially open as shown in FIGURE 9 at 300 degrees. The inlet portcontinues to enlarge until it is again wide open 6 at zero degrees inFIGURE 4. Thus it can be said that the motor cavity is initiated at 180degrees and increases through zero to a maximum at degrees when theoutlet port again begins to open, turning it into an exhaust cavity.

The sequence can be summarized as follows:

At 270, inlet area begins to open.

At 0, inlet area is wide open.

From 0 to 60, inlet area is constant.

From 60 to 120; inlet area gradually closes.

At 120, inlet area is fully closed.

At 120, outlet area begins to open at the bottom.

At 210, outlet area is wide open.

From 210 to 330, outlet area is constant.

From 330 to 120, outlet area gradually closes.

At 120, outlet area at the top cavity is fully closed.

With this timing and sequence the inlet port admits suflicient fluid toprovide the necessary power for the full design load while allowing thefull useful expansion of the fluid down to a practical exhaust pressure,and the inlet is fully out 01f as the outlet port begins to open.

A better understanding of the variation in pressure occurring under theblade 74 in relation to the cycling of the inertia ring 32 is obtainedfrom the following explanation. First of all, if an outlet port isdisposed substantially at right angles to a flow channel, a flowing offluid through the flow channel will produce a vacuum or pressurereduction adjacent such outlet port. Conversely, if a pressurized fluidis contained within but not permitted to flow through the flow channel,it will be observed that the pressurized fluid will flow into andthrough the outlet port. Thus, it will be readily understood that whenthe inlet port 70 is open and pressurized fluid is being supplied intothe work chamber via the inlet port 70, the rate of flow through passage48 will be relatively high thereby producing a relative drop in pressureunder the blade 74. However, even under these circumstances the pressureunder the blade will be slightly greater than the pressure existingwithin the working chamber thereby causing the blade to exert apredetermined amount of force against theinner surface of the inertiaring 32 to effect a seal at the point or along the line of contact. Itwill be understood that by proper design an effective seal will beobtained even though only a few ounces of force is exerted by the bladeagainst the inertia ring. Further, this force will vary depending on thevariation in pressure beneath the blade 74. When the inlet ports 62 and70 are closed, all of the pressure of the compressed fluid is directedunder the blade causing the blade to move against the inertia ring withconsiderable force. It has been found that the change in pressure underthe blade occurs gradually, the amount of change being relative to theopening of the inlet ports 62 and 70. It has also been found that duringthat portion of the cycle in which the inlet ports are closed, the innersurface of the inertia ring 32 disposed opposite the upper portion ofthe blade 74 moves outwardly relative to the outer surface of the core12 adjacent the slot 72 in which the blade 74 is disposed and that thepressure under the blade 74 increases and is timed coincidentally to theblades outwardly motion. When the blade is required to move radiallyinwardly within the slots formed in the core 12 due to the changingposition of the inertia ring, the pressure beneath the blade decreaseswhile at the same time the area of the inlet port opening into the workchamber is increased. The foregoing is more easily visualized byexamining FIGURES 7, 8 and 9 which show the radially outwardly movementof the blade during which time the inlet port is closed or substantiallyclosed, and the radially inwardly movement of the blade in FIG- URES 4,5 and 6 during which time the inlet port opening into the chamber 30degreases from a partial open condition to a closed condition.

With respect to a comparison between the orbital velocity of the inertiaring and the expansion velocity of the pressurized fluid within theworking chamber, it has been found that when the back pressure orexhaust pressure is maintained approximately one-half of the pressure ofthe pressurized fluid at the inlet and the fluid is propelled throughthe working chamber under the influence of its own capacity to expand,the compressed fluid will expand at a fixed velocity relative to thetemperature of the fluid. Further, where the fluid is propelled only byits own capacity to expand, it has been found that the orbital velocityof the inertia ring can be maintained equal to or slightly greater thanthe velocity of such expansion and thus through the use of apredetermined configuration and positioning of the inlet and outletports, the end walls, and the valving of the ports by the orbiting ofthe inertia ring, it is possible to maintain the rate of fluid expansionequal to or slightly less than the orbital velocity of the inertia ring.Thus, the volume of the fluid at any instant in time is substantiallythe same as the volume of the working chamber for the same instant oftime and there is no instigation for volume increase of the workingchamber which would result in the inertia ring contacting the exteriorsurface of the core 12.

Referring now to FIGURE 4, it is easy to visualize the starting of theapparatus where the orbital position of the inertia ring is as depictedtherein. However, the position of the inertia ring may very well bychance be other than as shown in FIGURE 4, for instance see the positionas shown in FIGURE 7. Where the inertia ring is in the position as shownin FIGURE 7, the inlet ports are fully closed. When the inlet ports areclosed, all of the fluid pressure is directed into the slot under theblade. As a consequence, a suflicient force is generated against theblade causing it to lift the ring into the starting position as shown inFIGURE 4. At the same time sufficient fluid flows through channel 88 andthe slot 72 to cause an increase in the volume of the working chamberthereby initiating counterclockwise rotation of the inertia ring priorto the actual opening of the inlet ports.

The apparatus is designed to develop a constant external amplitude ofmotion over a wide range of external loads, producing maximum inertiaring eccentricity during maximum resistance and reduced eccentricityduring reduced resistance. When the resistance against the apparatus isdecreased, the frequency of the cycle of operation is increased. Thishigher frequency reduces the expansion time available for the fluidduring the angular generation of the motor cavity, and therefore theinstantaneous fluid volume and consequently the cavity volume will beless at any given instant. This is illustrated in FIGURES 10 and 11which show the positions of the inertia ring at the zero and 180 degreestages. It will be noted that the gap 40 is considerably larger at thelower load. Also the lesser eccentricity of the ring reduces the maximumopening of the inlet and outlet port-s, thus automatically reducing thequantity of fluid expended. The eccentric or spiral arrangement of theinlet and outlet ports also automatically adjusts the timing of inletand exhaust for maximum efliciency, and compatibility with the loadsituation within the load capacity of the apparatus.

Since the inertia ring is always held spaced from the core by the fluidpressure in the minimum gap, the ring need not actually rotate about itsaxis as the prior art devices were required to do. Consequently it isfeasible to secure the barrier blades to the inertia ring with a pivotalconnection to insure that they always remain in sealing relation. Asseen in FIGURE 12, the core 106 is basically similar to core 12 ofFIGURE 1 and is provided with a similar slot 108. Barrier blade 110 isslidably mounted therein, and its outer end fits into notch 112 in theinertia ring 114 in sealing relation. It is connected thereto forrocking motion by pivot pin 116 carried by the inertia ring. The motionand operation are just the same as in the embodiment previouslydescribed.

It will be apparent to those skilled in the art that various changes maybe made in the construction and operation of the apparatus as disclosedwithout departing from the spirit of the invention, and it is intendedthat all such changes shall be embraced within the scope of thefollowing claims.

I claim:

1. Apparatus for generating vibrations comprising: a fixed, spool-shapedsupporting member having a central axially directed cylindrical core andlaterally extending end walls defining a work chamber; an inertia ringsurrounding said core Within said work chamber and having an innerdiameter greater than the outer diameter of said core to permitoscillatory movement of said inertia ring in all directions radial ofsaid core; a barrier blade extending longitudinally of said core andmounted therein for sliding movement radially thereof in sealingengagement with said ring and arranged to define the initial point of amotor cavity of a variable volume and peripheral extent between saidcore and said inertia ring and the end point of an exhaust cavity ofvariable volume and peripheral extent between said core and said inertiaring; a pressure fluid inlet port in an end wall communicating with saidwork chamber on the motor side of said blade; a pressure fluid outletport in an end wall communicating with said work chamber on the exhaustside of said blade; said inlet port being in the form of an elongatearcuate slot extending along the inner face of the end wall andoriginating adjacent said barrier blade; said outlet port being in theform of an elongate arcuate slot extending along the inner face of theend wall and terminating adjacent said barrier blade; said inlet porthaving a substantially constant maximum opening during approximatelysixty degrees of travel of said inertia ring; said outlet port having asubstantially constant maximum opening during approximately one hundredtwenty degrees of travel of said inertia ring; said inertia ring beingadapted to oscillate about said core in an orbital path with at leastone of its end faces acting as a valve to open and close cyclically andsuccessively said inlet and outlet ports; the opening of said inlet portserving to admit fluid to enlarge the motor cavity and provide thedriving force for said inertia ring; the opening of the exhaust portserving to discharge fluid to decompress the exhaust cavity; both ofsaid ports being so located in the path of orbital movement of saidinertia ring as to be cyclically substantially covered and partiallyuncovered by the adjacent end face of the inertia ring in its orbitalmovement.

2. Apparatus as claimed in claim 1; the beginning of the period ofmaximum opening of said outlet port oc curring about one hundred fiftydegrees after the ending of the period of maximum opening of said inletport.

3. Apparatus for generating vibrations comprising: a fixed, spool-shapedsupporting member having a central, axially directed cylindrical coreand laterally extending end walls defining a work chamber; an inertiaring sur rounding said core within said work chamber and having an innerdiameter greater than the outer diameter of said core to permitoscillatory movement of said inertia ring in all directions radial ofsaid core; a barrier blade extending longitudinally of said core andmounted therein for sliding movement radially thereof in sealingengagement with said ring and arranged to define the initial point of amotor cavity of variable volume and peripheral extent between said coreand said inertia ring and the end point of an exhaust cavity of variablevolume and peripheral extent between said core and said inertia ring; apressure fluid inlet port in an end wall communicating with said workchamber on the motor side of said blade; a pressure fluid outlet port inan end wall communicating with said work chamber on the exhaust side ofsaid blade; means to supply pressure fluid to said inlet port; saidinertia ring being adapted to oscillate about said core in an orbitalpath with at least one of its end faces acting as a valve to open andclose cyclically and successively said inlet and outlet ports; theopening of said inlet port serving to admit fiuid to enlarge the motorcavity and provide the driving force for said inertia ring; the openingof the exhaust port serving to discharge fluid to decompress the exhaustcavity; and a radially extending fluid inlet port disposed in said corecommunicating with the work chamber adjacent to said blade and on themotor side thereof to serve as an auxiliary pressure fluid supply duringthe period when the inlet port in said end wall is closed; said inletport in said core being in communication with said means to supplypressure fluid.

4. Apparatus for generating vibrations comprising: a fixed, spool-shapedsupporting member having a central, axially directed cylindrical coreand laterally extending end walls defining a work chamber; an inertiaring surrounding said core within said work chamber and having an innerdiameter greater than the outer diameter of said core to permitoscillatory movement of said inertia ring in all directions radial ofsaid core; a barrier blade extending longitudinally of said core andmounted therein for sliding movement radially thereof in sealingengagement with said ring and arranged to define the initial point of amotor cavity of variable volume and peripheral extent between said coreand said inertia ring and the end point of an exhaust cavity of variablevolume and peripheral extent between said core and said inertia ring,the outer edge of said barrier blade being pivotally connected to theinner face of said inertia ring; a pressure fluid inlet port in an endwall communicating with said work chamber on the motor side of saidblade; a pressure fluid outlet port in an end wall communicating withsaid work chamber on the exhaust side of said blade; and means to supplypressure fluid to said inlet port; said inertia ring being adapted tooscillate about said core in an orbital path with at least one of itsend faces acting as a valve to open and close cyclically andsuccessively said inlet and outlet ports; the opening of said inlet portserving to admit fluid to enlarge the motor cavity and provide thedriving force for said inertia ring; the opening of the exhaust portserving to discharge fluid to decompress the exhaust cavity.

5. Apparatus for generating vibrations comprising: a fixedlongitudinally extending axle member having a centrally located axiallydirected enlarged cylindrical core; a pair of end plates on said axlemember extending laterally at the ends of said core to define therewitha cylindrical work chamber; an inertia ring surrounding said core withinsaid work chamber and having an inner diameter greater than the outerdiameter of said core to permit oscillatory movement of said inertiaring in all directions radially of said core; a casing surrounding allof said component and having a closed end defining a first expansionchamber at a first end of said axle member; said axle member having alongitudinal fluid passage therethrough communicating at said first endwith said first expansion chamber; a conduit connected to a source offluid pressure and with the fluid passage in the axle member at thesecond end of said axle member; a longitudinally and radially extendingslot in said core; a barrier blade mounted in said slot for radialmovement; the outer free edge of said blade being straight and smoothand adapted to contact the inner surface of said inertia ring in sealingengagement at all times during operation to define the initial point ofa motor cavity of variable volume and peripheral extent between saidcore and said inertia ring and the end point of an exhaust cavity ofvariable volume and peripheral extent between said core and said inertiaring; a pressure fluid inlet port in each end wall communicating withsaid work chamber on the motor side of said blade; a pressure fluidoutlet port in each end wall communicating with said work chamber on theexhaust side of said blade; a second expansion chamber in said axlemember adjacent the second end of the axle member and comprising aportion of the longitudinal fluid passage; each of said inlet portscommunicating with its adjacent expansion chamber to receive pressurefluid in which the major portion of the velocity energy has beentransformed to expansion potential; the slot in said core communicatingwith said longitudinal passage to receive pressure fluid for urging saidblade into contact with said inertia ring; said ring being adapted tooscillate about said core in an orbital path with its end faces actingas valves to cyclically and successively open and close said inlet andoutlet ports; the openings of said inlet ports serving to admit fluid toenlarge the motor cavity and provide the driving force for said inertiaring; and the openings of the exhaust ports serving to discharge fluidto decompress the exhaust cavity.

6. Apparatus for generating vibrations in which a hollow cylindricalweight in the form of an inertia ring is movable in an orbital pathabout a centrally located cylindrical core having a diameter less thanthe internal diameter of the inertia ring and characterized by:

a partition dividing a work chamber defined between the core and thering into two cavities of variable volume;

said partition including a blade mounted in a longitudinally extendingslot formed in the core for radial sliding movement therein;

a fluid inlet port and a fluid outlet port which are opened and closedcyclically in response to movement of the ring relative to the core topermit one of the cavities to be subjected to fluid pressure and theother to be exhausted;

end walls defining walls of the work chamber, said inlet port and saidoutlet port being formed in at least one of the end walls, said inertiaring and said blade having axial lengths slightly less than the axialdistance between the end Walls so that the inertia ring and the bladeare separated from each of said end walls by a clearance; and

means including auxiliary ports formed in said end walls for supplyingfluid pressure to said clearances to prevent physical contact betweenthe end walls and the end faces of the inertia ring and blade.

7. Apparatus for generating vibrations comprising: a fixed, spool-shapedsupporting member having a central, axially directed, hollow,cylindrical core and laterally extending end walls defining a workchamber, said core having a longitudinally extending slot formedtherein; an inertia ring surrounding said core within said work chamberand having an inner diameter greater than the outer diameter of saidcore to permit oscillatory movement of said inertia ring in alldirections radial of said core; a barrier blade extending longitudinallyof said core and mounted Within said slot for sliding movement radiallythereof in sealing engagement with said ring and one of the surfaces ofsaid slot to define the initial point of a motor cavity of variablevolume and peripheral extent etween said core and said inertia ring andthe end point of an exhaust cavity of variable volume and peripheralextent between said core and said inertia ring; means for supplyingpressurized fluid through said slot into said motor-cavity; a pressurefluid inlet port in an end wall constructed to be disposed inintermittent communication with said motor cavity; a pressure fluidoutlet port in an end wall constructed to be disposed in intermittentcommunication with said exhaust cavity the orbital movement of said ringeffecting opening and closing of said inlet and outlet ports; and meansfor moving, during operation of the apparatus, said inertia ringorbitally relative to said core while maintaining at all times duringoperation of the apparatus a predetermined amount of minimum separationbetween opposed surface portions of said ring and said core, said meansfor moving said inertia ring orbitally relative to said core includingmeans for supplying to said inlet port for introduction into said motorcavity, during at least approximately one-half of each cycle, apredetermined amount of fluid of substantially constant pressure andwithout substantially any linear mass velocity whereby the volume offluid supplied to said motor cavity in combination with the increase involume of fluid occurring from expansion of the fluid within said motorcavity equals, during pressurization of the motor cavity, theinstantaneous volume of said motor cavity, said outlet port whendisposed in communication with said exhaust cavity effecting anexhaustion of said exhaust cavity.

8. Apparatus as claimed in claim 7; said inlet port being in the form ofan elongate arcuate slot, said arcuate slot being eccentric to saidcore, with the end of the slot adjacent to the barrier blade beingcloser to said core than is the opposite end of the slot.

9. Apparatus as claimed in claim 8; the peripheral extent of saidarcuate slot being approximately 60 degrees.

10. Apparatus as claimed in claim 7; said outlet port being in the formof an elongate arcuate slot, said arcuate slot being eccentric to saidcore, with the end of the slot adjacent to the barrier blade beingcloser to said core than is the opposite end of the slot.

11. Apparatus as claimed in claim 10; the peripheral extent of saidoutlet port slot being approximately 180 degrees.

12. Apparatus as claimed in claim 7; said ports being so arranged withrespect to each other that initiation of the opening of the inlet portoccurs aproximately one hundred eighty degrees after completion ofclosure of the outlet port.

13. Apparatus for generating vibrations comprising:

a supporting member having a hollow core with a longitudinally extendingslot formed in a wall portion thereof and end walls defining a workchamber;

an inertia ring surrounding said core within said work chamber andhaving an inner diameter greater than the outer diameter of said core topermit oscillatory movement of said inertia ring in all directionsradial of said core;

a barrier blade mounted for sliding movement substantially radiallywithin the slot of said core and being adapted to contact in sealingengagement the inner surface of said inertia ring and a surface portionof said slot at all times during operation to define the initial pointof a motor cavity of variable volume and peripheral extent between saidcore and said inertia ring and the end point of an exhaust cavity ofvariable volume and peripheral extent between said core and said ring;

means for supplying pressurized fluid through said slot into said motorcavity;

a pressure fluid inlet port in an end wall communicating with said motorcavity;

a pressure fluid outlet port in an end wall communicating with saidexhaust cavity and having intermittent communication with said motorcavity;

said inertia ring being adapted to oscillate about said core in anorbital path with at least one of its end faces acting as a valve tocyclically and successively open and close said inlet and outlet ports;

means for moving said inertia ring orbitally relative to said coreincluding means for supplying to said inlet port for introduction intosaid motor cavity, during at least approximately one-half of each cycle,a predetermined amount of fluid of substantially constant pressure andwithout substantially any linear mass velocity whereby the volume offluid supplied to said motor cavity in combination with the increase invol ume of fluid occurring from expansion of the fluid within said motorcavity equals, during pressurization of the motor cavity, theinstantaneous volume of said motor cavity;

said outlet port, when disposed in communication with said motor cavity,effecting at least a partial decompression of said motor cavity, andsaid outlet port, when disposed in communication with said exhaust port,effecting an exhaustion of said exhaust cavity.

14. Apparatus for generating vibrations in which a hollow cylindricalweight in the form of an inertia ring is movable in an orbital pathabout a centrally located cylindrical core within said ring having adiameter less than the inner diameter of the inertia ring, a workchamber thus being formed between the ring and the core;

slot means formed in said core;

a partition disposed within said slot means and dividing the workchamber into two cavities of variable volume, one of said cavities beinga motor cavity and the other being an exhaust cavity, said partitionbeing disposed in sealing engagement with said slot means and a surfaceof said ring;

means for supplying pressurized fluid through said slot means into saidmotor cavity;

said work chamber having a fluid inlet port in communication with saidmotor cavity and a fluid outlet port in intermittent communication withsaid motor cavity and said exhaust cavity; said ports being opened andclosed cyclically in response to movement of the ring relative to thecore to permit:

(i) the motor cavity to be subjected to fluid pressure and at leastpartially decompressed; and (ii) the exhaust cavity to be exhausted;said apparatus being characterized by:

means for orbitally moving said inertia ring relative to said coreduring operation of the apparatus, including means for supplying to saidinlet port for introduction into said motor cavity, during at leastapproximately /2 of each cycle, a predetermined amount of fluid ofsubstantially constant pressure and without substantially any linearvelocity whereby the volume of fluid supplied to said motor cavity incombination with the increase in volume of fluid occurring fromexpansion of fluid within said motor cavity equals ,duringpressurization of the motor cavity, the instantaneous volume of saidmotor cavity;

said outlet port effecting (i) at least a partial decompression of saidmotor cavity when disposed communication therewith; and

(ii) an exhaust of said exhaust cavity when disposed in communicationtherewith.

15. Apparatus as defined in claim 14 in which the inlet port originatesadjacent one side of the partition and the outlet port terminatesadjacent the other side of he partition.

16. Apparatus as described in claim 14 in which an expansion chamber islocated upstream of said inlet port.

17. Apparatus as defined in claim 14 in which end walls are providedwhich define walls of the work chamber, the inlet port and the outletport being formed in at least one of said end walls.

18. Apparatus as described in claim 17 in which the inlet port is anelongate arcuate slot formed in one end wall adjacent the path oforbital movement of the adjacent end face of the inertia ring such thatthe inlet port is subsantially covered by said end face duringapproximately one-half of each orbital cycle of the inertia ring.

19. An apparatus for generating vibrations comprising:

end walls and an inertia ring located therebetween and having alongitudinally extending, arcuately shaped surface;

a member having a longitudinally extending, arcuately shaped surface;

a work chamber formed between the arcuately shaped surfaces and said endwalls;

means for eccentrically oscillating said inertia ring about said memberso that at any given time a given portion of the arcuately shapedsurface of said inertia ring is close to a given portion of thearcuately shaped surface of said member, to thereby form a continuouslymoving small gap between said inertia ring and said member;

a slot formed in said member;

a barrier disposed Within said slot and in sealing engagement with botha surface of said slot and said inertia ring, said barrier bladecooperating, at any given time during operation of the apparatus, withsaid gap to divide the work chamber into:

(i) a motor cavity commencing adjacent one side of said barrier andterminating at said gap; and

(ii) an exhaust cavity commencing adjacent said gap and terminatingatthe other side of said barrier; said barrier being constructed fortranslatory movement in a direction generally radially of the arcuatelyshaped surface of said member, both cavities, during operation of theapparatus, being of variable volume varying between substantially zeroand the substantial volume of the work chamber;

means for supplying pressurized fluid through said slot into said motorcavity;

a fluid inlet port in a wall of said work chamber and constructed to bedisposed in intermittent communication with the motor cavity;

a fluid outlet port in a wall of said work chamber and constructed to bedisposed in intermittent communication with the motor and exhaustcavities, said oscillatory movement of said inertia ring effectingopening and closing of said inlet and outlet ports;

said means for moving said inertia ring orbitally relative to saidmember including means for supplying to said inlet port for introductioninto said motor cavity, during at least approximately one-half of eachcycle, a predetermined amount of fluid of substantially constantpressure and without substantially any linear mass velocity whereby thevolume of fluid supplied to said motor cavity in combination with theincrease in volume of fluid occurring from expansion of the fluid withinsaid motor cavity equals, during pressurization of the motor cavity, theinstantaneous volume of said motor cavity;

said outlet port effecting:

(i) at least a partial decompression of said motor cavity when disposedin communication therewith, and

(ii) an exhaustion of said exhaust cavity when disposed in communicationtherewith.

20. An apparatus as described in claim 19 including means for movingsaid inertia ring radially during a predetermined portion of each cycleof said ring, said means including said barrier and means for supplyingpressurized fluid against a surface portion of said barrier.

21. A method for generating vibrations by means of a device of the typein which an inertia ring is mounted for cyclic orbital movement relativeto a member to form a work chamber between opposed surfaces of theinertia ring and the member, there being a barrier mounted between theopposed surfaces of the ring and the member for translatory movementwith respect to one of said opposed surfaces, wherein said barrier is insealing engagement with the other one of said opposed surfaces to dividethe work chamber into a motor cavity commencing adjacent one side ofsaid barrier and an exhaust cavity terminating at the other side of saidbarrier; said method comprising the steps of:

orbitally moving said inertia ring relative to said member by means ofpressurized fluid;

maintaining a predetermined amount of minimum separation between theopposed surfaces of said ring and said member at all times during suchmovement; and

supplying a predetermined amount of fluid to the motor cavity during atleast approximately onehalf of each cycle, said fluid being supplied atsubstantially constant pressure without substantially any linear massvelocity, the volume of said fluid equaling the instantaneous volume ofthe motor cavity whereby the increased volume of fluid, duringpressurization of said motor cavity, occurring from expansion of thefluid within said motor cavity substantially equals the increased volumeof the motor cavity during movement of the ring.

22. Apparatus for generating vibrations comprising: a fixed,spool-shaped supporting member having a central, axially directed,hollow, cylindrical core and laterally extending end wall defining awork chamber, said core having a longitudinally extending slot formedtherein; an inertia ring surrounding said core within said work chamberand having an inner diameter greater than the outer diameter of saidcore to permit oscillatory movement of said inertia ring in alldirections radial of said core; a barrier blade extending longitudinallyof said core and mounted within said slot for sliding movement radiallythereof in sealing engagement with said ring and one of the surfaces ofsaid slot and arranged to define the initial point of a motor cavity ofvariable volume and peripheral extent between said core and said inertiaring and the end point of an exhaust cavity of variable volume andperipheral extent between said core and said inertia ring; a pressurefluid inlet port in each end wall communicating with said work chamberon the motor side of said blade; a pressure fluid outlet port on eachend wall communicating with said work chamber on the exhaust side of aidblade; the two inlet ports being of the same size and in the samerelative position with respect to the motor side of said work chamberand the two outlet ports being of the same size and in the same relativeposition with respect to the exhaust side of said work chamber; andmeans to supply pressure fluid to said inlet ports and through said slotinto said motor cavity; said inertia ring being adapted to oscillateabout said core in an orbital path with its end faces acting as a valveto open and close cyclically and successively said inlet and outletports; the opening of said inlet ports serving to admit fluid to enlargethe motor cavity and provide the driving force for said inertia ring;and the opening of the exhaust ports serving to discharge fluid todecompress the exhaust cavity.

23. Apparatus as described in claim 22; said inertia ring having anaxial length slightly less than the actual distance between said endWalls to provide a clearance between the ring and said end walls; said.inlet ports being of such size and location that the end faces of saidinertia ring at least partially overlies same at all times; said inletports serving to supply pressure fluid to said clearances to preventphysical contact between the end walls and the end faces of said inertiaring.

24. A method of operating a vibration generator of the type in which awork chamber is defined by the volume between two end Walls, a coremember, and an inertia ring surrounding said core member, said workchamber being divided into a motor cavity and an exhaust cavity by abarrier blade, and wherein fluid is intermittently introduced into saidmotor cavity so as to cause said inertia ring to undergo oscillatorymovement in all directions radial of said core member so that said motorand exhaust cavities have a variable volume depending upon the relativepositions of said barrier blade and the nearest point of said inertiaring to said core member; and including means for intermittentlydirecting fluid from said exhaust cavity out of an outlet port afterhaving been directed into said inlet port of said motor cavity throughaffluid supply conduit, said method comprising the steps 0 convertingthe kinetic energy of the fluid supplied to said conduit to potentialenergy by reducing the linear mass velocity of said fluid tosubstantially zero before introducing said fluid into said inlet port byexpanding said fluid into an expansion chamber; and introducing a volumeof fluid into said motor cavity at any given time so that the thuslyintroduced volume of fluid substantially equals the instantaneous volume15 of said motor cavity at said given time, whereby said inertia ringmaintains a substantially continuously spaced relationship from saidcore member as said inertia ring undergoes said oscillatory movement.

25. The method of claim 24 including the steps of changing the directionof said fluid by about 90 at least two times between entry of said fluidinto said conduit and introduction of said fluid into said motor cavity.

26. A method. of operating a vibration generator of the type in which awork chamber is defined by the volume between two end walls, a coremember, and an inertia ring surrounding said core member, said workchamber being divided into a motor cavity and an exhaust cavity by abarrier blade; and wherein fluid i intermittently introduced into saidmotor cavity so as to cause said inertia ring to undergo oscillatorymovement in all directions radial of said core member so that said motorand exhaust cavities have a variable volume depending upon the relativepositions of said barrier blade and the nearest point of said inertiaring to said core member, and including means for intermittentlydirecting fluid from said exhaust cavity out of an outlet port afterhaving been directed into said inlet port of said motor cavity through afluid supply conduit, said method comprising the steps of:

converting the kinetic energy of the fluid supplied to said conduit topotential energy by reducing the linear mass velocity of said fluid tosubstantially zero before introducing said fluid into said inlet port,and

providing an exhaust back pressure at said exhaust port of aboutone-half the pressure of said fluid at said inlet port, whereby saidinertia ring maintains a substantially continuously spaced relationshipfrom said core member as said inertia ring undergoes said oscillatorymovement.

UNITED STATES PATENTS References Cited 2,763,472 9/1956 Fontaine.

3,162,426 12/ 1964 Fontaine.

FOREIGN PATENTS 1,207,855 9/ 1959 France.

WALTER A. SCHEEL, Primary Examiner JOHN M. BELL, Assistant Examiner US.Cl. X.R. 7487

